1. Field of the Invention
The present invention relates to electrolytic ionized water, and more specifically, relates to a manufacturing method and an apparatus of strongly alkaline ionized water.
2. Description of the Related Art
Alkaline water produced by electrolysis of water, i.e., alkaline ionized water, has been known. As an apparatus and a method for producing the alkaline ionized water, a continuous method has been known, in which alkaline water is produced by continuously supplying an electrolysis solution to an electrolytic bath. The conventional technique can be roughly classified into the following two methods.
One of them uses an electrolytic bath having a three-cell configuration. That is, the electrolytic bath is separated by two diaphragms to have an electrolysis solution cell at the center, having on both sides an anode cell and a cathode cell, and electrodes provided in both the anode cell and the cathode cell. A supplying line of tap water or pure water is connected to inlets of the anode cell and the cathode cell, a withdrawing line of acidic water is connected to an outlet of the anode cell, and a withdrawing line of alkaline ionized water is connected to an outlet of the cathode cell. An electrolysis solution bath is provided outside, and its outlet is connected to an inlet of the electrolysis solution cell via a circulating pump, so that the electrolysis solution is circulated and supplied to the electrolysis solution cell.
The other one of them uses an electrolytic bath having a two-cell configuration. Specifically, an electrolytic bath is separated by one diaphragm to an anode cell and a cathode cell. A supplying line of an electrolysis solution is connected to inlets of the anode cell and the cathode cell, a withdrawing line of acidic water is connected to an outlet of the anode cell, and a withdrawing line of alkaline ionized water is connected to an outlet of the cathode cell.
In the conventional technique, a large amount of water can be produced by continuously supplying an electrolysis solution to an electrolytic bath to simultaneously obtain alkaline ionized water and acidic water, but there are the following problems.
The first problem is that it is difficult to produce, without any problem, alkaline ionized water having a high pH value. In the case where an electrolytic bath having the two-bath configuration, the electrolysis solution is continuously exhausted from the outlet through the cathode cell of a path form, and therefore the time where an electrolytic voltage is applied to the electrolysis solution is a period where the electrolysis solution passes between the electrodes, which is extremely short.
In the case where an electrolytic bath having the three-cell configuration, an electrolysis solution in the central electrolysis solution cell is electrolyzed to transfer a cation to water in the cathode cell through the diaphragm to produce alkaline ionized water. Since raw material water (tap water or pure water) supplied from an inlet of the cathode cell is continuously exhausted from an outlet of the cathode cell through the cathode cell of a path form, the cation is transferred from the electrolysis solution to the raw material water in an extremely short period of time where the raw material water passes between the electrodes.
In both cases, therefore, the pH value of the alkaline ionized water thus produced becomes low. Accordingly, alkaline ionized water for drinking can be produced, but it is difficult to produce water having a high pH value, which is effective as a detergent and a disinfectant.
When the concentration of the electrolysis solution is increased as a countermeasure against the problem, an electrolysis solution containing a chloride ion in a high concentration is electrolyzed, and a problem arises in that a large amount of gas having a strong irritative smell is generated on the side of the anode cell. When the supplying amount of tap water or pure water is reduced as another countermeasure against the problem, a part of the electric energy for electrolysis is converted into heat energy to increase the temperature of the electrolysis solution, and electrolysis for a long period of time cannot be conducted due to the load on the diaphragm. Therefore, even when an electrolytic bath having the three-cell configuration, in which an electrolysis solution of a high concentration can be used, is used, the pH value of alkaline ionized water that can be industrially produced is 12.0 or less.
The second problem is that when an electrolytic bath having the three-cell configuration is used, and pure water is used as raw material water considering the quality of alkaline ionized water, the pure water is also used for the production of the by-product acidic water. Since pure water is relatively costly water, from which anions and cations are removed, the production cost of the alkaline ionized water is increased.
The third problem is that the pH value of the thus produced alkaline ionized water widely varies, and it is difficult to stably produce alkaline water having a constant pH value. That is, in the conventional technique, the electrolytic current changes depending on the change of the concentration of the electrolysis solution and the change of the liquid temperature, and unevenness is enhanced, for example, alkaline ionized water having a high pH value or alkaline ionized water having a low pH value is obtained in summer or in winter.
The production method of alkaline ionized water includes a batch method, in addition to the continuous methods. In this method, an electrolysis solution stored in an electrolytic bath is electrolyzed in a period of time to produce alkaline ionized water, and the resulting alkaline ionized water is withdrawn from the electrolytic bath. Thereafter, an electrolysis solution is again stored in the electrolytic bath to be electrolyzed in a period of time.
In this conventional technique, since an electrolytic voltage is applied under the conditions in that the electrolysis solution is stored in the electrolytic bath, alkaline ionized water has a higher pH value than in the case of the continuous method by arbitrarily setting the time of applying voltage. However, it involves problems in that since the capacities of the cathode cell and the anode cell of the electrolytic bath are limited, the ratio of production amounts of alkaline ionized water and acidic water cannot be arbitrarily changed; the pH values of alkaline ionized water and acidic water cannot be freely controlled; and in order to produce large amounts of alkaline ionized water and acidic water, the electrolytic bath storing the electrolysis solution and its incidental equipment must be large scaled, resulting in that the whole apparatus becomes large scaled.